The Great Core Training Debate: Abdominal Hollowing vs. Abdominal Bracing
In the past few years, the manner in which to go about incorporating core conditioning into one’s workout regime or sport-specific training continues to be debatable in the world of biomechanics research. Below is a brief introduction to your “Core” and its importance in improving daily function and maximizing athletic training.
Core stability is a key contributor in maximizing efficient athletic function by ensuring the proper sequential activation of muscle tensing (contractions) to perform a specific athletic task. Virtually every activity that uses the extremities such as: strength training, golfing, running, kicking and throwing benefit from a conditioned core to maximize force generation in the extremities, minimize joint loading, and prevent injury. Core conditioning deficiencies have been correlated with higher incidences of knee injuries and low back pain.
The core complex can be visualized as a cylinder – the diaphragm (a major respiratory muscle) as the lid, and the muscles of the pelvis at its base. This cylinder houses the bony structures of the spine, hips, pelvis, abdominal structures, and upper legs. Since the core is located centrally in the body, as its name implies, it provides the foundation of the body’s stability and balance. There are two commonly prescribed methods of achieving core stability:
1) Abdominal hollowing – commonly cued as “drawing-in of the navel to ward the spine and activating pelvic floor muscles by thinking of pulling the inner thigh muscles up behind the belly button, similar to performing a Ke gel exercise”
2) Abdominal bracing – “tightening the abdominal muscles as if preparing for a punch in the stomach”
Here enters the debate: As these cues are seemingly polar opposites, how can they both engage the core? Several years ago, it was deemed that abdominal hollowing activates primarily the deepest abdominal layer, known as the transverse abdominis and multifidus muscles, which was shown to decrease the incidence of low back pain and reduce the risk of subsequent low back injury. However, in light of the fact that the core’s role is to provide dynamic stability through movements rather than static uni-planar positions, recent studies have challenged the approach of simply focusing on activating a couple muscles and disregarding the input of many other of the muscles involved in creating stability. Abdominal bracing, therefore, tends to recruit torso co-contraction and promote greater spinal and trunk stability.
As either of the methods of hollowing or bracing tend to promote core conditioning, my take on this debate is multi-factorial. In the end, it really depends on the individual’s goals and presenting condition, whether they are ‘healthy’ or ‘injured’. The approach would be to assess whether the individual’s goal is stability, endurance or strength. Endurance for example would benefit from hollowing in static positions such as planking, whereas stability in movement-specific/sports would best be achieved through bracing.
As for which core exercises amongst the hundreds available are the most effective? Once again, the answer is not simple, as exercise programs need to be specific and suited to individual needs. A proper gait analysis and movement screen by a qualified health professional helps to point out areas of dysfunction and focus on a specific training program. To simply incorporate core training into your training time, be sure to attend a Core stability group class at your fitness center!